Sunday, December 27, 2009

Tuesday, December 22, 2009

The Turkish filbert, or Turkish hazel, (Corylus colurna) is in the Birch family. All members of the family have male and female catkins on the same tree. Here are the filbert's male catkins. They will hang on all winter and mature in the spring.

The leaves are cordate at the base and have double-serrate margins.

The corky outer bark is grey, but when it exfoliates, reveals reddish-brown inner bark.

The tree has a pyramidal form with most limbs perpendicular to the trunk.

The nuts are encased in a stiff, bristly husk called an involucre. They come in clusters, the involucres joined at the base.

Here are some nuts still on the tree in late summer.

And here's one of the filbert's guests. All of its visitors are harmless; the filbert is not susceptible to any major diseases or pests.

Just as I seemed to be getting better at identifying trees, they went and lost all their leaves. I've started to use bud and twig keys, but it will be a while before all of the buds stop looking the same to me.

Sunday, December 13, 2009

Tuesday, December 8, 2009

Taxodium distichum, like Metasequoia, is a deciduous conifer: unlike most cone-bearing trees, its changes color and drops its leaves in the fall. The feathery leaves are made of needles that appear two-ranked but are actually arranged spirally on branchlets.

The globular cones are covered with peltate scales.

Here are two bald cypresses side by side. The far one has turned red ahead of its neighbor.

Bald cypress has a conical shape when young. At maturity, it has a more cylindrical form with a rounded top. Bald cypress is also called swamp cypress because of its occurrence in low, wet land. When it grows near or in water, woody knobs protrude up from the roots. These "knees" were thought to help with oxygen intake, but the current dominant theory is that they help provide stability in loose substrates.

These cones are closer to maturity.

Behind each scale, there are two seeds. Although bald cypresses are known for their ability to live in flood-prone areas, seeds immersed in water will not germinate. Seedlings have to establish themselves in well-drained or saturated soil before they are able to survive in standing water.

New female catkins will emerge in the spring out of the pointed buds. Male flower buds (in the upper left corner) are long, scaly, and rounded at the tip. In the spring, they will grow into yellow male catkins.

Thursday, November 12, 2009

The persimmon (Diospyros virginiana) is native to the Southeastern United States. It's in the Ebony family and true to its family name, it has very dark (and very hard) wood. Persimmon wood has been used in golf clubs, bowling pins, and billiard cues.

The mature bark is distinctive; it's cracked into square plates.

But the most distinctive feature of the persimmon is the fruit. It looks like a small orange tomato with a large persistent calyx. The fruit is edible, but if eaten before ripe, can taste uncomfortably chalky. Usually it's ready to eat after a frost.

In "The Historie of Travaile into Virginia Britannia" (1612), William Strachey wrote of the fruit:

They have a plomb which they call pessemmins, like to a
medler, in England, but of a deeper tawnie cullour; they grow on
a most high tree. When they are not fully ripe, they are harsh
and choakie, and furre in a man's mouth like allam, howbeit,
being fully ripe, yt is a reasonable pleasant fruict, somewhat
lushious. I have seene our people put them into their baked and
sodden puddings; there be whose tast allowes them to be as
pretious as the English apricock; I confesse it is a good kind of
horse plomb.

Friday, November 6, 2009

Fossils indicate that the Ginkgo family is over 200 million years old. Ginkgo biloba is the only species living today in the entire division Ginkgophyta.

Ginkgoes are dioecious, meaning some trees are male and some are female. This particular group of trees is the product of asexual reproduction. An older gingko was cut down and new shoots came up around the stump.

As the stump decayed, the strongest shoots survived and grew into trees, forming a ring of ginkgoes.

-looking up from the center-

-cicada shell on ginkgo bark-

The leaves are set in whorls on short, slow-growing shoots.

They're green in the summer...

and turn yellow in the fall.

If you've ever walked by a female ginkgo around this time of year, you know why most cities only allow male ginkgoes to be planted along the streets: the fruit smells pretty bad. Some say rancid butter, but I didn't even know butter could go bad, so consulting my personal odor library, I can only say that it's reminiscent of stomach acid mixed with partially digested food.